Comprehensive testing strategy for jargons.dev ensuring code quality and reliability across all components.

• vitest - Modern testing framework with TypeScript support
• happy-dom - Browser environment simulation for testing
• @testing-library/jest-dom - DOM testing utilities and assertions
• @vitest/coverage-v8 - Code coverage reporting

• 161 tests across 7 test suites
• 99.4% overall test success rate (160 passing, 1 unrelated failure)
• 98.5% coverage on constants validation (constants.js)
• 95.34% coverage on crypto functions (src/lib/utils/crypto.js)
• 100% coverage on utility functions (src/lib/utils/index.js)
• Complete coverage on business logic functions (submit-word.js, word-editor.js, branch.js, fork.js)

npm run test          # Run all tests
npm run test:watch    # Run tests in watch mode
npm run test:ui       # Open Vitest UI interface
npm run test:coverage # Generate detailed coverage report

tests/
├── setup.js                     # Test environment configuration with MSW
├── fixtures/                    # Test data and API response mocks
│   ├── test-data/
│   │   └── index.js             # Sample words and repository details
│   └── github-responses/
│       └── index.js             # GitHub API response fixtures
├── mocks/
│   └── github-api.js            # MSW handlers for GitHub API endpoints
└── unit/
    ├── constants/
    │   └── constants.test.js     # Project constants validation
    ├── lib/                      # Business logic tests
    │   ├── submit-word.test.js   # PR creation and submission logic
    │   ├── word-editor.test.js   # Word file management operations
    │   ├── branch.test.js        # Git branch operations
    │   └── fork.test.js          # Repository forking logic
    └── utils/
        ├── crypto.test.js        # Encryption/decryption functions
        └── index.test.js         # Utility functions

• Utility Functions - Date calculations, string parsing, URL building, text formatting
• Crypto Functions - Encryption/decryption with security validation and error handling
• Constants Validation - Project configuration, labels, and SEO compliance

• Word management functions (submit-word.js, word-editor.js)
• Git operations (branch.js, fork.js)
• GitHub API interactions and error handling
• MSW (Mock Service Worker) integration for realistic API testing

• Phase 3: Component Tests (React components, Astro layouts)
• Phase 4: Integration Tests (API endpoints, data flow)
• Phase 5: End-to-End Tests (User workflows, browser testing)

• 39 test cases covering all 10 utility functions
• 100% coverage with comprehensive edge case testing
• Functions tested: date calculations, string parsing, URL building, text formatting

• 17 test cases with security-focused validation
• 95.34% coverage including round-trip validation and error handling
• Tests: encryption format validation, tampered data detection, edge cases

• 20 test cases ensuring proper structure and values
• 98.5% coverage with configuration validation
• Tests: PROJECT_REPO_DETAILS validation, LABELS consistency, SEO compliance

• 19 test cases covering PR creation and submission workflow
• 100% coverage of pull request title generation, template rendering, and label assignment
• Tests: PR title formatting, template substitution, repository parsing, GitHub API error handling

• 26 test cases covering word file management operations
• 100% coverage of word creation, updates, and retrieval
• Tests: base64 encoding, template processing, path normalization, special character handling

• 24 test cases covering Git branch management
• 100% coverage of branch creation, retrieval, and deletion
• Tests: branch reference formatting, repository parsing, complex ref handling, error propagation

• 16 test cases covering repository forking logic
• 100% coverage of fork detection, creation, and synchronization
• Tests: GraphQL queries, fork status checking, automatic updates, nested error handling

• Unit tests: *.test.js
• Integration tests: *.integration.test.js
• E2E tests: *.e2e.test.js

import { describe, it, expect } from "vitest";
import { functionName } from "../src/lib/utils";

describe("Function Group", () => {
  it("should handle basic case", () => {
    expect(functionName("input")).toBe("expected");
  });

  it("should handle edge cases", () => {
    expect(functionName("")).toBe("");
    expect(functionName(null)).toThrow();
  });
});

The test environment is configured in tests/setup.js with:

• Environment variable mocking for crypto keys
• GitHub configuration mocking
• DOM testing utilities setup
• MSW (Mock Service Worker) for GitHub API mocking
• Comprehensive test fixtures for GitHub API responses

# Run specific test file
npm test -- tests/unit/utils/index.test.js

# Run business logic tests
npm test -- tests/unit/lib/

# Run specific business logic function tests
npm test -- tests/unit/lib/submit-word.test.js

# Run tests matching pattern
npm test -- --grep "crypto"

# Run with coverage for specific files
npm run test:coverage -- --include="**/utils/**"

# Run tests in UI mode
npm run test:ui

Generate detailed coverage reports with:

npm run test:coverage

Coverage reports include:

• Line coverage percentages
• Branch coverage analysis
• Function coverage metrics
• Uncovered line identification

1. Follow existing patterns - Use established test structure and naming
2. Aim for high coverage - Target >90% coverage on new code
3. Include edge cases - Test error scenarios and boundary conditions
4. Use descriptive names - Test names should clearly describe what's being tested
5. Group related tests - Use describe blocks to organize test suites

• Test behavior, not implementation - Focus on what the function does
• Keep tests isolated - Each test should be independent
• Use meaningful assertions - Prefer specific expectations over generic ones
• Mock external dependencies - Isolate code under test from external systems
• Use MSW for API testing - Mock GitHub API endpoints for realistic testing scenarios
• Test error scenarios - Verify proper error handling and propagation chains

Track testing progress in our GitHub issues:

• #171: Phase 1 - Foundation Tests ✅
• #172: Phase 2 - Business Logic Tests ✅
• #173: Phase 3 - Component Tests
• #174: Phase 4 - Integration Tests
• #175: Phase 5 - E2E Tests

• Test environment setup (happy-dom)
• Coverage configuration
• Test file patterns and exclusions

• Environment variable mocking
• Test utilities initialization
• Global test configuration
• MSW server setup for API mocking

• Test data fixtures - Sample words, repository details, and configuration
• GitHub API responses - Realistic API response mocks for testing

• MSW handlers - GitHub API endpoint mocking for comprehensive testing

1. Phase 3 Implementation - Begin component testing for React/Astro components
2. Enhanced API Testing - Expand MSW coverage for additional GitHub API endpoints
3. Component Testing Framework - Set up React/Astro component testing infrastructure
4. CI/CD Integration - Add automated testing to deployment pipeline
5. Performance Testing - Add benchmarks for critical business logic functions